Computed tomography dataset virtual dissection for sternal re-entry in congenital cardiac surgery

In congenital heart surgery, redo-sternotomies are very common. In most cases, sternal re-entry is achieved without serious complications. However, sometimes elective institution of peripheral cardiopulmonary bypass is needed for safe sternotomy, albeit with a long cardio-pulmonary bypass time. We report our initial experience of three-dimensional reconstruction and virtual dissection of the retrosternal space, using Horos®, an open-source software, which uses the computed tomography (CT) scan dataset from a 64-slice CT pulmonary angiogram. We reconstructed three-dimensional images to help us conceptualize the retrosternal space for safer re-entry, which could be viewed in stereo with depth perception using anaglyph glasses. Once reconstructed, the substernal space could be viewed from multiple angles and this helped us better understand the anatomy for re-entry. The CT scans, though being the age-old imaging modality for assessment of the anatomy, leave room for assessment of the sub-sternal space. Recently, we encountered three patients in whom the sternal re-entry was deemed to be difficult. The CT scan left ambiguity in assessment of the substernal space and all three patients were assessed with 3-dimensional (3D) reconstruction and virtual dissection prior to sternotomy. All three patients underwent a safe redo-sternotomy without institution of cardiopulmonary bypass. Three-dimensional rendering of CT dataset as a novel technique has the potential to help surgeons visualize the retrosternal space in three dimensions and better understand the spatial relation of the heart with the inner table of the sternum.

The online version contains supplementary material available at 10.1007/s12055-024-01879-3.